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Michael "Z" Goddard 2018-05-07 11:09:45 -04:00
parent 2db2287d12
commit 8107349bec
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1 changed files with 139 additions and 82 deletions
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221
src/engine/execute.js
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@ -106,104 +106,161 @@ const handleReport = function (
*/
const RECURSIVE = true;
// With the help of the Blocks class create a cached copy of values from
// Blocks and the derived values execute needs. These values can be produced
// one time during the first execution of a block so that later executions
// are faster by using these cached values. This helps turn most costly
// javascript operations like testing if the fields for a block has a
// certain key like VARIABLE into a test that done once is saved on the
// cache object to _isFieldVariable. This reduces the cost later in execute
// when that will determine how execute creates the argValues for the
// blockFunction.
//
// With Blocks providing this private function for execute to use, any time
// Blocks is modified in the editor these cached objects will be cleaned up
// and new cached copies can be created. This lets us optimize this critical
// path while keeping up to date with editor changes to a project.
/**
* A execute.js internal representation of a block to reduce the time spent in
* execute as the same blocks are called the most.
*
* With the help of the Blocks class create a mutable copy of block
* information. The members of BlockCached derived values of block information
* that does not need to be reevaluated until a change in Blocks. Since Blocks
* handles where the cache instance is stored, it drops all cache versions of a
* block when any change happens to it. This way we can quickly execute blocks
* and keep perform the right action according to the current block information
* in the editor.
*
* @param {Blocks} blockContainer the related Blocks instance
* @param {object} cached default set of cached values
*/
class BlockCached {
constructor (blockContainer, cached) {
/**
* Block operation code for this block.
* @type {string}
*/
this.opcode = cached.opcode;
const BlockCached = function (blockContainer, cached) {
this.opcode = cached.opcode;
this.fields = cached.fields;
this.inputs = cached.inputs;
this.mutation = cached.mutation;
/**
* Original block object containing argument values for static fields.
* @type {object}
*/
this.fields = cached.fields;
this._isHat = false;
this._blockFunction = null;
this._definedBlockFunction = false;
this._isShadowBlock = false;
this._shadowValue = null;
this._fields = null;
this._argValues = null;
this._inputs = null;
/**
* Original block object containing argument values for executable inputs.
* @type {object}
*/
this.inputs = cached.inputs;
const {runtime} = blockUtility.sequencer;
/**
* Procedure mutation.
* @type {?object}
*/
this.mutation = cached.mutation;
const {opcode, fields, inputs} = this;
/**
* Is the opcode a hat (event responder) block.
* @type {boolean}
*/
this._isHat = false;
// Assign opcode isHat and blockFunction data to avoid dynamic lookups.
this._isHat = runtime.getIsHat(opcode);
this._blockFunction = runtime.getOpcodeFunction(opcode);
this._definedBlockFunction = typeof this._blockFunction !== 'undefined';
/**
* The block opcode's implementation function.
* @type {?function}
*/
this._blockFunction = null;
const fieldKeys = Object.keys(fields);
/**
* Is the block function defined for this opcode?
* @type {boolean}
*/
this._definedBlockFunction = false;
// Store the current shadow value if there is a shadow value.
this._isShadowBlock = fieldKeys.length === 1 && Object.keys(inputs).length === 0;
this._shadowValue = this._isShadowBlock && fields[fieldKeys[0]].value;
/**
* Is this block a block with no function but a static value to return.
* @type {boolean}
*/
this._isShadowBlock = false;
// Store a fields copy.
this._fields = Object.assign({}, this.fields);
/**
* The static value of this block if it is a shadow block.
* @type {?any}
*/
this._shadowValue = null;
// Create a argValues instance for all executions of this block. Fields are
// static, store them on args.
this._argValues = {
mutation: this.mutation
};
for (const fieldName in fields) {
if (fieldName === 'VARIABLE') {
this._argValues.VARIABLE = {
id: fields.VARIABLE.id,
name: fields.VARIABLE.value
};
} else if (fieldName === 'LIST') {
this._argValues.LIST = {
id: fields.LIST.id,
name: fields.LIST.value
};
} else if (fieldName === 'BROADCAST_OPTION') {
this._argValues.BROADCAST_OPTION = {
id: fields.BROADCAST_OPTION.id,
name: fields.BROADCAST_OPTION.value
};
} else {
this._argValues[fieldName] = fields[fieldName].value;
}
}
/**
* A copy of the block's fields that may be modified.
* @type {object}
*/
this._fields = Object.assign({}, this.fields);
// Store a modified inputs. This assures the keys are its own properties
// and that custom_block will not be evaluated.
this._inputs = Object.assign({}, this.inputs);
delete this._inputs.custom_block;
/**
* A copy of the block's inputs that may be modified.
* @type {object}
*/
this._inputs = Object.assign({}, this.inputs);
if ('BROADCAST_INPUT' in this._inputs) {
this._argValues.BROADCAST_OPTION = {
id: null,
name: null
/**
* An arguments object for block implementations. All executions of this
* specific block will use this objecct.
* @type {object}
*/
this._argValues = {
mutation: this.mutation
};
const broadcastInput = this._inputs.BROADCAST_INPUT;
if (broadcastInput.block === broadcastInput.shadow) {
// Shadow dropdown menu is being used.
// Get the appropriate information out of it.
const shadow = blockContainer.getBlock(broadcastInput.shadow);
const broadcastField = shadow.fields.BROADCAST_OPTION;
this._argValues.BROADCAST_OPTION.id = broadcastField.id;
this._argValues.BROADCAST_OPTION.name = broadcastField.name;
const {runtime} = blockUtility.sequencer;
delete this._inputs.BROADCAST_INPUT;
const {opcode, fields, inputs} = this;
// Assign opcode isHat and blockFunction data to avoid dynamic lookups.
this._isHat = runtime.getIsHat(opcode);
this._blockFunction = runtime.getOpcodeFunction(opcode);
this._definedBlockFunction = typeof this._blockFunction !== 'undefined';
// Store the current shadow value if there is a shadow value.
const fieldKeys = Object.keys(fields);
this._isShadowBlock = (
!this._definedBlockFunction &&
fieldKeys.length === 1 &&
Object.keys(inputs).length === 0
);
this._shadowValue = this._isShadowBlock && fields[fieldKeys[0]].value;
// Store the static fields onto _argValues.
for (const fieldName in fields) {
if (
fieldName === 'VARIABLE' ||
fieldName === 'LIST' ||
fieldName === 'BROADCAST_OPTION'
) {
this._argValues[fieldName] = {
id: fields[fieldName].id,
name: fields[fieldName].value
};
} else {
this._argValues[fieldName] = fields[fieldName].value;
}
}
// Remove custom_block. It is not part of block execution.
delete this._inputs.custom_block;
if ('BROADCAST_INPUT' in this._inputs) {
// BROADCAST_INPUT is called BROADCAST_OPTION in the args and is an
// object with an unchanging shape.
this._argValues.BROADCAST_OPTION = {
id: null,
name: null
};
// We can go ahead and compute BROADCAST_INPUT if it is a shadow
// value.
const broadcastInput = this._inputs.BROADCAST_INPUT;
if (broadcastInput.block === broadcastInput.shadow) {
// Shadow dropdown menu is being used.
// Get the appropriate information out of it.
const shadow = blockContainer.getBlock(broadcastInput.shadow);
const broadcastField = shadow.fields.BROADCAST_OPTION;
this._argValues.BROADCAST_OPTION.id = broadcastField.id;
this._argValues.BROADCAST_OPTION.name = broadcastField.value;
// Evaluating BROADCAST_INPUT here we do not need to do so
// later.
delete this._inputs.BROADCAST_INPUT;
}
}
}
};
}
/**
* Execute a block.